1. Technical Field
The present invention relates to a semiconductor device and a manufacturing method.
2. Related Art
Conventionally, in a semiconductor device such as an IGBT, a trench gate structure is known, as shown in Patent Document 1, for example.
Patent Document 1: Japanese Patent Application Publication No. H08-255902
A semiconductor device such as an IGBT preferably has a prescribed threshold voltage corresponding to its function or the like.